1. Field of the Invention
The present invention relates generally to a system for attenuating undesired commercial messages during radio broadcasting, and more specifically, to a circuit which attenuates radio frequency signals when voices are broadcasted without accompanying background music.
2. Description of the Related Art
U.S. Pat. No. 4,292,467 relates to a device for providing improved control mechanisms for electronic devices containing a number of mechanical adjusting means.
U.S. Pat. No. 4,506,377 discloses a device for providing a spoken-instruction controlled system for an automotive vehicle which can activate a series of actuators after a spoken instruction has been recognized by a speech recognizer.
U.S. Pat. No. 5,107,539 relates to a device for providing automatic sound volume control for use with automobile audio equipment.
U.S. Pat. No. 5,170,490 relates to improving radio transmission and receiving functions using voice compression.